.ui-button-icon-primary.ui-icon.icone-valider { 
  background-image: url("../images/icone_valider.png"); 
  width: 22px;
  height: 22px;  
}

.ui-button-icon-primary.ui-icon.icone-refuser {
  background-image: url("../images/icone_refuser.png");
  width: 22px;
  height: 22px;
}